Method of and apparatus for electric welding.



C. A. CADWILL METHOD DE AND APEARATUS EDR ELECTRIC WELDING.

APPLICATION FILED JUNE 2, |917.

Patented J au. 7, M19.

f77 F Ole Affi yes .L J3.. ...'...s-e

for e i .n.te t" Mi. se.. .someten CHARLES CDWELL, 0F CLE'VEL-ill, OHIG, ASSEGTOE T THE ELECTRLC RALWAY IMPROVEMEN' CMPAl/, GF CLEELANB, HO, A CORPORATION' F G3310.

METEO@ QE MTE APPARATUS FOR ELECTRC WELDNG.

To all whom may concern:

Be it known that I, CHARLES A. CAD- y/ELL, a citizen of the United States, and e resident of Cleveland, county o" otiyaiioge, and State of Ohio, beve inventetl a nen7 and. useful Improvement in Methods o1 and Apparatus for Electric 'Welding of which the following is a specification, the principle of the invention being` herein explained and the best mode in which I lieve contemplated epplying that principle, sees te distinguish it from other inventions. Q

The object of the present invention is to provide an apparatus whereby e current oi relatively high voltage may be utilized in Welding one inetei part to another. Thus,

yfor exemple, in Welding, bruing, or other- Wise homogeneously uniting rail bonds onto rails7 current of the voltage regularly useol in the operation of an electric railway may be tiken from the trolley without requiring the interposition of e transformer. Here tofore, in operations of this sort, it bes beenA found necessary to utilize en electrode of high' resistentie materiel, bringing; the seme to the re 'uisite high temperature by pessing tlieretnrougb e current oi reletiveiy ioW voltage and large emjperege. in tiie pres ent process, insteeei orreiying open resistance of such en eiectrocie, ll ntilize. the electric ere which, es is Weil understood, 'wiii conducts considerably higher voltage than just inciieeteii for sr'ii resistence electrode.

As pointed ont, however, in my co-pentiing application ifieti Jene i9 lili-5, Ceriei No. 35,0%, eonsioierebie fiitieulty loes lier/etofor@ been enconntere in attempting to eine ploy the electric are for time Weiding bodies together, particularly Where the boeiies are of unlike mess and where in. adfiition., there exists si disparity in the temperature of 'fir sion, thesmeile'r mass, for exemple, having; Tooth tbe oejer temperature fusion anni the greater heet conductivity. l'n such e cese, an ordinery are, es is Well initie: ood, wili fuse or burn suela smaller body before the contacting face or" the larger bociy is brought to e Welding temperature; enti, it tiie parte are Welded togetiier et eil, they ere thus united only at e few points insieed of throughout their contacting surfaces, :is is desirable particularly in e ruil bonding' op eration, Where'tlie object is to Provide an.

ipeoficeton of Letters Patent.

Application lle. iut-.e 52, '3.9M'.

lby iine time,

gert or the IPeftenteti effen. ft', ll'i semi ne.

adequate as Weil es e permanent electrical connection, across the joint between tbetwo rails.

As in tbe aforesaid cio-pending applies tion, I utilize in the present improved roc ess en apparatus consistingof the com inetion with e. beet distributing plete, adapted to Contact with the articleto be' heated, of Ineens for directing en are against, and spreading such are over tbe surface of such plete, salti Ineens including an electro-megu netie coii suitably disposed with respect to the ere. in the present cese, iiowever,in steed of utilizing one of the articles being heated. soecicelly the rail, as e part of tbe return circuit, engi thus requiring but e sinw rie electrode proper, employ two elemc trenes, since li beve found that by e proper disposition of these with respect toi-tbe perte being Welded, it is possible to see'eresstis fectory results. Y

The steps end ineens constituting,Y in' vention Wili 'oe hereinafter :fiiliy described;

end particularly pointed out in the cleiins the annexed drawing and iollowinfgxdescrisi' tion setting forti; in detail certain stepsiene' epperatusembodying the invention, which, however, constitute but one of the serious Ways in which the gorinciple of tile invention .may oe used.

in seid annexe@ firewingzm Figure i is e pien View ei? en eppersus suitable 'for out my present improved process or method; :53 is eiierizontel sectional View 4oi time seine; (is. 3 enel 4 ere respeetrveiy Si e and :irontele vetions thereof i? ii is e vertieei transn verse 'section n on the elaine indicate@ 6 is e, 'View more or ieee iiieg'reinnietie in eneiecter illustmtinp; one operative disposition ot tie epperetus; Fig. -Vis e simiier View iiiuien treating enot er rlispoeition thereof.

fiiere, inst' mi oi? eieeicying e singgieeiee trede, end e J "l c :teriierm of the boriies r e empioy tivo eiect. ocles, so es to en en etc between. tbe seme which is ceuseti 'ey' ineens oit' e, megnetie .tieiti or otberwiee, to ietereiiy play against tbe soci?. botiies, {oi e beet distribnti pietre eonteet there with), e. serions oiini euity encoiintereti in that lie portion o the body, or such. plete,-

- e'. e., positive electrode, so that the first-nieny,inserted the two electrodes 6.

tioned portion of such article or plate becomes more highly heated than the other portion thereof. The result is that it has been found very dillicult, if not practically iin-v possible, to ei'iiect a uniform. Weld, or homogeneous juncture, of the contacting surfaces of the two bodies over a suliieient area to satisfy the requirements of rail bonding.

l; have found, however, that in the case oic a rail bond, where it is the 'terminal only that is being welded, and wherethe body oi' the bond lies to one side or the other of such terminal, heat is conducted inuch more rapidly away from the portion of the terminal thus contiguous to the main body off'the bond than from the extreme portion of such terminal. bonds are ordinarily made of copper, which has a'high rate of heat conductivity, so that this may be iliade a factor in the process, as

will now be explained.

What l accordingly do is to so locate the' two 4electrodes between which the arc is established with reference to the portions of the rail bond terminal, thus contiguous to and farthest removed from the .inain body ot the bond as to always have the negative electrode adjacent such lrstmained portion ol the terminal. l have found that the wastage of heat, by conduction through the body ot the bond from this portion of the terminal, will then approximately absorb the excess heat generated at the end or" this electrode,

and so balance the heating eect throughout the bond terminal, with the resultI that the latter. is substantially uniformly heated throughout.

The illustrative apparatus shown in the drawingsconsists simply of a heat-distribue ing plate l., preferably of graphite, which is adapted to contact with the article to be heated, specifically the bond terminal 2, (Figs. 3f o and?) in the case in hand, in combination `with a heat conserving chainber, the rear wall 3 of which consists preferably of a magnesite block or plate, while the convergingside walls 4 are made of graphite or clay, old Crucible stuft' being well'suited for the purpose. The platel' is removably attached either by mechanical means or a clay cement to the front edges of theside walls et, so as to close the eliamber, While the rear wall 3 is pierced by the apertures 5 inclined equally to the median line of the chamber, through which may be The latter will ordinarily consist ot' carbon pencils, either of cylindrical form or rectangular cross-section, as found best in the particular instance. Suitably attached to the rear wall, between theapertures through which the electrodes- It will be `understood that theseI leaders are thus inserted, is an electro-magnetic @oil ".7 with its axis preferably lying in the median line of the device, and, as indicated in Figs. 5 and 7, the conductor 8, through which the current is supplied to the electrodes from the D. C. generator 9, forms the coil of this electroanagnet. rlhis electro-magnet will tend .to deflect the arc that is established between the two electrodes so as to increase its heating efl'cct on the plate, and at the saine time 'will spread such are over the surface of the plate so as to heat a larger 'area than would otherwise be the case. The chamber formed by theback and side walls 3 and it serves, oi'

` course, to conserve the heat thus. developed and prevent waste through radiation.

F or supporting this chamber and appurtenant parts in proper relationto the work,

any 'suitable means may be employed. ln 'i the ease of a` bonding operation such sup-- porting means convenientlyl takethe :torniv of an elongated traine 10, such as shownv in Figs. l, 2, 3 and il, to the extremities ot which are .attached clamps il, that arey adapted to suitably engage with the rail 1,3, while adjusting nuts l2 combined with coinpression springs lll serve .to hold the frame with the plate resting against the one bond terminal 2 under any desired degree of pressure. l

ln setting up the` foregoing apparatus,

after the frame has been secured in place in the fashion just described, the electrodes 6 are inserted through the apertures provided for the purpose inthe back wall 3 of the chamber, so that their inner ends are brought to the desired degree of proximity to each other and the plate l, the negative electrode y being inserted through thelaperture nearest, to the body l5 of the bond, as illustrated in 6. ln this way the balancing of the heating eilect, to which reference has been' made above, is secured. 'When the other terminal .of the bond isto he welded, the frame lis shifted, of course, to properly locate the plate l against such other tern .minah and the electrodes are removed and re-inse'rted in reverse position so as to still secure the desired uniform heating effect,

as illustrated in Fig. 'i'.

Other modes of applyinge the principle of my invention may be employed instead of the one explained, 4change ,beingn made as regards the steps or mechanism herein disclosed, 4provided the ineans stated by any of the following claims or the equivalent oi? I ytherefore particularly point outand distinctlv claim as my invention 1. The method of electrically heating a body, one portion of which tends to heat yless rapidly than hnother, which consists iisl ' such stated meansbe employed.

of such body tending thus to heat less rap idly.

2. The method of electrically Welding or brazing a bond terminal to a rail, the portion of such terminal contiguous to the ber; a heat-distributing plate adapted to contact with the article to be heated and forming one Wall of said chambfr; and two electrodes extending' Within said ohambe into proximity to said plate. 4. In apparatus of the character descr1hcd,the combination of a heat conserving chan'iber; a heat-distributing plate adapted to contact with the article to be heated and forming one wall of said chamber; vand two electrodes extending Within said chamber into proximity to said plate, said electrodes being interchangeable, substantially as and for the purpose specied.

5. In apparatus of the character described, the combination of a heat conserving chamber; a heat-distributing plate adapted to contact With the article to be heated and forming one Wall of said chamber; two convergent electrodes extending within said chamber into proximity to said plate; and an electro-magnetic coil disposed with its axis von a line between said electrodes.

6.1m apparatus of the character described, the combination of a heat Conservn ing chamber; a heat-distributing plate adapted to vContact with the article to be heated and forming one Wall of said chainu ber; two convergent electrodes extending within said chamber into proximity to said plate; an electro-'magnetic coil disposed with its axis on a line between said electrodos; and current supply connections for said electrodes, said coil being included in series therein.

Signed by me this th day of May, Zi91'l`.

CHARLES A. CALDWELL. 

